Switch operating mechanism



Nov. 23, 1948. p. REPKA SWITCH OPERATING HECWISI 2 Sheeta-Sheet 1 FiledSept. 7, 1944 5 m u lllll' 00 z aw in W I 1" 6 m 4 a m 9 7 h z a. w w m{7 l L v Q 3 4 R 6 m m V N NOV. 1948- P. T. REPKA 2,454,341

SWITCH OPERATING MECHANISM Filed Sept. 7, 1944 2 Sheets-Sheet 2 mug/walf t/Z \7 MMA ML MIL Pas ed Nov. 23. 1948 SWITCH OPERATING MECHANISM PaulT. Repka, Freeport, Ill., alsignor to First Industrial Corporation,Wilmington, Del., a

corporation of Delaware Application September '7, 1944, Serial No.552,063

UNITED "STATES PATENT OFFICE between the structure on which the switchis mounted and the moving element whichoperates the switch may vary innew structures and later as a result of wear or strain may vary furtherfrom time to time. Accordingly, it is necessary in the design of such aswitch that it be capable of some adjustment when placed in newassemblies and that it be capable of further adjustment from time totime during use; I have found from experience that where switches ofthis character are used in places where extensive vibration ocours, asin airplanes and in tanks, the abovementioned adjustments, if made withthe aid of screws, nuts, etc., are apt to be unsatisfactory, as suchdevices are themselves frequently jarred loose by prolonged vibration.

Accordingly, I have in this invention provided means for adjusting anovertravel switch permitting it to be readily adjusted afterinstallation and during use and avoiding the difficulties produced byloosened screws or nuts. 3

One of the objects of my invention is to provide adjustment means forovertravel switches which will be of the utmost simplicity inconstruction.

Another object of the invention is to provide means for adjustment of'anovertravel switch, not requiring the use of wrenches and requiring nomore than such a simple tool as a screwdriver or other instrumentsuitable for bending a piece of metal.

Another object of the invention is to provide adjustment means in anovertravel switch which can easily be altered after the switch isinstalled and so designed that the adjustment feature willitself not getout of adjustment.

The foregoing and other objects and advantages of the invention willbecome apparent from .a perusal of the specification and drawings inwhich I have described and shown, in order to illustrate the nature ofthe invention, one embodiment thereof, which is at present a preferredform of construction.

Referring now to the drawing:

Fig. 1 is a side elevation of an overtravel switch having mountedthereon an actuator arm made in accordance with my invention.

Fig. 2 is a top plan view with a part thereof broken away showing theassembly appearing in Fig. 1.

Fig. 3 is a plan view of the restoring spring employed to keep theactuator arm elevated.

Fig. i is a vertical longitudinal sectional view of the actuator armshown in Fig. 1.

Fig. 5 is an end view of the actuator arm assembly as viewed from theleft from Fig. 4.

Fig. 6 is a longitudinal sectional view of the actuator arm showing oneof the adjustment tabs slightly bent to change the adjustment of theswitch. Here. the free position of the arm is not altered, but thebending of the tab, as

shown, downwardly will cause the switch to operate upon a lesserdownward movement of the arm.

Fig. 7 is a longitudinal sectional view of the actuator arm showing bothadjustment tabs, to be later described, in their normal position and,diagrammatically, a striker element in position to strike the roller onthe actuator arm.

Fig. 8 is a sectional view of the actuator showing both adjustment tabsbent from their normal position causing the free position of the arm tobe somewhat lower and the operating point for the witch to occur at asomewhat lower angular position of the arm than would be the case of theunadjusted device shown in Fig. 7. I

Fig. 9 shows no adjustment on the tab which controls the free positionof the arm but it retains the same adjustment on the other tab as doesFig. 8. Fig. 10 is another longitudinal sectional view of the actuatorarm showing the small tab bent downwardly as in Fig. 8 to lower the freeposi- I tion of the arm and the other tab bent downwardly as in Fig. 6.

Referring further to the drawing, as this invention is not concernedwith the construction of the contact mechanism itself in the switch. itis sufllcient here to show only the housing I and the reciprocableplunger 2 extending from the housing and which operates the switchmechanism contained within the housing, a suitable switch being one suchas disclosed in U. S. Patent No. 1,960,020, to McGall.

To support the actuator arm I provide a U-shaped bracket generallyindicated as l in which the arm is pivotally supported on the pintle 4extending through the bracket. The bracket spans the housing of theswitch and is secured thereto by bolts 3a, the bracket having a centraltop portion lb. A sleeve 5 surrounds the pintle and two depending earson opposite sides of the arm such as the ear 6 engage the sleeve I. Thearm consists of the channel shaped member I on which the aforesaid earsare formed and the bracket 0 secured by rivets 9 and It to attests theouter end thereof for-supporting: the roller In order to restore the arml to its uppermost or tree position there is provided the spring it(Fig. 3) having loops i2a. wrapped around the sleeve ii, an intermediateportion i222 bearing against the top of the housing iand legs ilcbearing against the underside of the arm l.

When the arm is in its tree position it may either bump against the edgethe bracket 8 as shown in Fig. '7 or its free position may be loweredsomewhat by bending the tab it downwardly as shown in Figs. 8 and 10.Such an adjustment will lower the position of the roller relatively tothe striking piece which is sym bolized by the element l6, and which ofcourse may be any moving structural element intended to operate such aswitch. The entire arm and supporting bracket are (made of sheet metalsteel: so that the tab may be bent dorm to any desired positie on itwith a screw small pair of pliers or by using some other similarinstrument. The sheet metal employed is however oi such strength andrigidity that it does not flex or bend appreciably under the forces towhich it is nomally subjected in use. Therefore, when such adjustment ismade it cannot fall out oi adiustnent due to some oi the usual causessuch as vibration as might happen ill adjustment involved the use oi ascrew or nut.

For operating directly on the plunger 2 of the switch I provide a postit extending through a tab it, having on its lower end an enlargedportion or collar ll for retaining the spring it under com pressionagainst the under side of the tab it. A small collar it at the upper endof the post prevents it from being disengaged from the tab it.

Referring to Fig. i, if the actuator arm be rotated downwardly by theaction of an exterior force the tab it acting through the spring itagainst the collar it on the post it will depress the plunger 2. whichitself is usually spring loaded, and thus actuates the switch at apreselected operating point in the travel of the a. Further downwardtravel of the actuator arm may occur but thereafter the plunger 2 mayengage astop within the housing or the bottom end of the post it maystrike the top oi the switch housing, but due to its spring mounting inthe tab it the post will not oppose further downward movement of thearm, but will merely slide through the tab.

Upon upward release of the arm l the spring it will res-tore it to itsfree position and the lower end of the post will be disengaged from. theplunger 2.

It will now be apparent that while the tab ill may be bent to vary thefree position of the arm and consequently the pretravel of the armbefore th post engages the plunger and operates the switch, the tab itmay be bent upwardly or downwardly to alter the particular angularposition or operating point of the actuator arm at which operation ofthe plunger 2 will occur.

I! tab it be bent upwardly, as shown in Figs. 8 and 9. the post It willnot move the plunger 2 a sufll-cient distance to operate it until thearm has been rotated downwardly a greater angle than 2 to its operatingposition upon less angularmovement of the arm l. Since this tab islikewise made of sheet metal it can be bent with a easy. and permanentadjustment without the use or special tools is a desirable objective inthese devices.

As was stated above the present invention does not involve the contactmechanism operated by the plumber 2. The actuator arm shown in thedrawing is arranged to apply the operating force to a plunger havingonly a short travel, as would be required in a snap switch of thecharacter shown in said Mclilall patent, but may be used with switcheswhose oper'atirie plungers have more or less travel than McGallsplunger.

The construction and arrangement of parts herein shown and described isat present the preicrred form of this invention, but it should beunderstood that some modification in the parts and in the details ofconstruction are contemplated.

and may be employed, without departing from the spirit and scope or theinvention defined in the following claims.

Having shown and described my invention, I claim:

1. An over-travel actuator for a plunger operated electric switchcomprising a bracket for attachment in a fixed position relative to thehousinc oi the switch, an actuator arm pivotally sup ported on saidbracket for rotation toward and away from the switch to operate thesame, a. metal member carried by and integral with said arm shapedandpositioned to be bendable with respect to said am, and means supportedon said member for contacting the plunger to operate the switch. thebending of said member relatively to said arm being arranged to alterthe angular position of the arm on its pivot at which the plunger isactuated.

2. An actuator for a plunger operated electric switch comprising abracket for attachment in a fixed position relative to the housing ofthe switch, an actuator arm pivotally supported on said bracket, a metalmember carried by and integral with said arm shaped and positioned to bebendable with respect to said arm, means supported on said member forcontacting the plunger to operate the switch, the bending of said memberrelatively to said arm being arranged to alter the angular position ofthe arm on its pivot at which the plunger will be actuated, and abendable metal tab disposed between said arm and a fixed portion of saidbracket for regulatably establishing the at rest angular position orsaid arm.

3. An actuator for an electric switch having a reciprocable plunger foroperating the contact mechanism thereof, comprising a bracket rigidlyconnectable with the switch in which said plunger is located, anoperating arm pivotally mounted on said bracket, a member carried bysaid am and a post supported on' said member arranged to contact the endor said plunger, means for resiliently supporting said post on saidmember to permit the post to yield after contacting and operating saidplunger, said member being bendable relatively to the arm in order tovary the eiiective force for operating the switch.

4. An .actuator for a plunger operated electric 1 said arm, and a springloaded post yieldably supported on said second tab for contacting andoperating said plunger, the second tab being bendable relatively to thearm to vary the angular position about the pivotal point of said armwhere said post will operate said plunger.

5. An'actuator for a plunger operated electric switchcomprising anovertravel arm, means for pivotally supporting the arm on a fixed axisfor rotation toward and away from the plunger, means on said arm to becontacted by an external force for rocking said arm on said switch,means carried by said arm for contacting the plunger to operate it, anda bendable metal tab on said am for supporting the last said means, saidtab being bendable by manually applied force at the time of installationof the switch or actuator to adjust the angular position of the arm atwhich the plunger will be operated.

6. An actuator for a plunger operated electric switch comprising agenerally U-shaped bracket secured to the housing of the switch, anovertravel operating arm pivot-ally supported within said U-shapedbracket at a fixed distance from the switch housing, a metal tabintegral with said bracket and bendable for determining the at restposition of said arm and for varying it, plunger operating overtravelmeans carried by said arm for contacting the plunger oi the switchswitch comprising an overtravel operating arm,

and means for supporting said plunger operating means on said arm, saidsupporting means including a cantileverly mounted metal element travelmovement of the am after operation of V the switch, and means forsupporting said plunger operating means on said arm including a memberreadily bendable upon installation by manually applied force for therebyselectively determining the angular position of the arm at which saidplunger will be operated and the amountot overtravel 01'- said arm.

'8. An actuator for a plunger operated electric switch comprising aU-shaped bracket for attachment at a fixed position relatively to andspanning the switch housing, an actuator arm pivotally supported withinsaid bracket, and overtravel means carried by the arm to contact andoperate the plunger. said mean including an element bendable by manuallyapplied force whose bending determines selectively the ang'ular positionat which the arm operates theplunger, and a member yieldablymounted onsaid element to permit 6 further angular movement of the. arm beyond theposition necessary to operate the plunger? 9. An overtravel actuator fora. plunger operated electric switch comprising an overtravel operatingarm, andmeans for pivotally supporting one end of said arm at a fixedposition with respect to the switch plungensaid means including a tabbendable for variably limiting the at rest position of said arm, abendable tab integrally carried by said arm, a spring loaded postyieldably supported on said second tab for contacting and operating saidplunger, the second tab bein bendable with respect to the arm to varythe angular position about the, pivot point of said arm where said postwill operate said plunger, and spring means for urging the arm to the atrest position. t g

10. An actuator for a plunger operated electric switch comprising anoperating arm, means for pivotally supporting said am at a fixed axisfor rotation toward and away from the plunger between an at restposition and an overtravel position, spring loaded overtravel means onsaid I arm positioned to engage the'plunger at a preselected positionafter preliminary free movement thereof upon rotation of the arm towardthe plunger to operate the latter yieldable to permit overtravelmovement of the arm, a tab on the arm for carrying the overtravel meansbendable by manual force to preselect the position of the arm at whichthe overtravel means engages the plunger, and a bendable tab between thearm and the bracket to preselect the at-rest position of the arm tothereby preselect the operating point of the arm relative to theplunger, and spring means for moving the arm to the at-rest position.

11. An actuator for a plunger operated switch comprising a U-shapedbracket spanning the switch and having the sides thereof attached to theopposite sides of the switch housing to support the center portion ofthe bracket in fixed spaced relation to the plunger and switch housin anactuator arm comprising a sheet metal strip pivoted between the sides ofthe bracket below, the center portion having a free end for rotation ,ofthe arm toward the plunger by an externally applied force, a tab on saidarm defined by a U-shaped cut intermediate the sides of said arm abovethe plunger, a spring loaded overtravel means mounted on said tab foroperating the plunger, yieldable for overtravel movement of the arm, thetab being bendable with respect to the arm by manually applied force topreselect the operating position of the arm, a tab integral with thecentral portion'of the bracket engageable by the arm and bendable bymanually applied force to preselect the rest position of the arm, and

spring means disposed between the housing and the arm forurging the armto the rest position.

, PAUL T. REPKA.

'nnrnna'uoas crran The following references are of-record in the- NumberName Date 847,555 Craft L Mar. 19, 1907 1,682,549 Billerbeck Aug. 28,1928 1,869,646 Anderson Aug; 2, 1932 1,969,488 Wagar Aug. '1, 19342,146,146 Innis Feb. 7, 1939 2,185,683 Barrett et a1. Jan. 2, 19402,260,964 Wilms Oct. 28, 1941 2,338,365 Thor-p et a1. Jan. 4, 1944

